WARNING ON MALE REPRODUCTIVE HEALTH

The Danish Environmental Protection Agency in Copenhagen,
Denmark released a report April 18th entitled MALE REPRODUCTIVE
HEALTH AND ENVIRONMENTAL CHEMICALS WITH ESTROGENIC EFFECTS. The
175-page English-language report, which we have obtained, says
male reproductive health is deteriorating in many countries, and
that the most likely cause is exposure to low levels of
industrial chemicals that contaminate food, water, and many
consumer products.

The Danish report says many industrial chemicals mimic sex
hormones (chiefly the female hormone, estrogen) and thus
interfere with the normal development of creatures (including
humans) that become exposed before, or shortly after, birth. The
report identifies many consumer products as sources of such
hormone-like chemicals: pesticides, detergents, cosmetics,
paints, and packaging materials, including plastic containers and
food wraps. [1] The report calls for an aggressive, coordinated
international research effort to describe the extent of the
problem, and to design programs of "prevention and intervention."

Meanwhile in the U.S., the Chemical Manufacturers Association
(CMA) has funded a report by a scientist who says these problems
are not real. "The suggestion that industrial estrogenic
chemicals contribute to an increased incidence of breast cancer
in women and male reproductive problems is not plausible," the
CMA's 6-page study concludes. [2]

In contrast, the Danish report says, "It is now evident that
several aspects of male reproductive health have changed
dramatically for the worse over the past 30-50 years. The most
fundamental change has been the striking decline in sperm counts
in the ejaculate of normal men; recent evidence from Paris
indicates that this decrease amounts to about two percent per
year over the last two decades. The result is that many,
otherwise normal, men now have sperm counts so low that their
fertility is likely to be impaired. Over the last half-century,
the incidence of testicular cancer has increased progressively in
many countries to become now the most common cancer in young men.
Other disorders of the male reproductive tract may also be
increasing in incidence, with several European countries
reporting a progressive rise in hypospadias (a malformation of
the external genitalia) and an apparently emerging trend towards
an increasing incidence of testicular maldescent [undescended
testicles]....

"While the etiologies [causes] underlying these apparent changes
are currently not clear, both clinical and laboratory research
suggest that all of the described changes in male reproductive
health appear inter-related and may have a common origin in fetal
life or childhood. This means that the increase in some of the
disorders seen today originated 20-40 years ago and that the
prevalence of such defects in male babies born today will not
become manifest for another 20-40 years or more," the report says.

The Danish report was prepared by 19 scientists and physicians,
including 13 from Denmark, two from France, one from England, one
from Scotland, and two from the U.S.

The report says that declining reproductive health has also been
widely observed in wildlife: "Trends in the reproductive health
of species other than man also raise the possibility of
environmental factors as partial etiologic [causal] contributions
in a decline noted in the male reproductive health of wildlife.
For example, wild panthers in the United States have been
reported to have an increase in undescended testes and a decrease
in semen quality, whereas male alligators in some lakes in
Florida have been shown to have abnormalities in their sex
hormone levels (tending towards femaleness) and to have smaller
than normal genitalia. Male fish in some parts of the United
Kingdom have been shown to express a 'female-like response' when
studied in a relatively natural setting. Earlier studies of fish
eating birds in the United States demonstrated nests containing
male hatchlings that were apparently feminized. A recent report
of lactating [milk-producing] male fruit bats suggested that the
males were, in some way, exposed to a female sex hormone. Recent
laboratory studies showed that when estrogenic forms of
polychlorinated biphenyls (PCBs) were painted on turtle eggs, the
male hatchlings were sex-reversed to females. Taken together,
this growing body of evidence suggests that environmental factors
that resemble female sex hormones may be having an adverse effect
on the reproductive capacity and wellbeing of diverse species,"
the report says.

The report summarizes evidence indicating that all of these
problems have a common origin: the exposure of male fetuses to
estrogen-like chemicals before birth. "The wealth of
experimental [laboratory animal] results and associated clinical
[human] reports suggests strongly that prenatal exposure to
exogenous [external] estrogens may play an etiologic role in the
trends observed in male reproductive health," the report says.

The report lists many ways in which humans become exposed to
chemicals that mimic hormones: "Estrogen effects are not
restricted to a small group of therapeutic agents but appear in
several groups of compounds that are in daily use in industry,
agriculture or in the home," the report says. "A major problem
is determining which chemicals are estrogenic... At present, tens
of thousands [of] man-made chemicals are used, yet the effects on
the endocrine [hormone] system have been studied for only a few
of these. The estrogenic activity of most chemicals (e.g.,
alkylphenols, phthalate esters, bisphenol-A) has been detected by
accident, not by intent; that is, no systematic screening, even
on individual groups of chemicals, has been attempted. Hence it
is highly possible that other estrogenic chemicals remain
unidentified... Thus, the present situation is that man and
wildlife are exposed to a very wide range of chemicals, and for
the majority of them we do not know whether these chemicals are,
or are not, estrogenic, whether their effects are additive, or
even what the true exposure to these chemicals is."

The report points out that even weakly estrogenic chemicals may
be of concern if they remain in the bodies of humans and wildlife
for long periods. Natural hormones are created by the body,
circulate in the blood stream very briefly to carry out a
particular task, and are then destroyed by natural mechanisms.
In contrast, many industrial chemicals that enter the body are
not readily broken down so they circulate in the blood for long
periods --in some cases many years --mimicking natural hormones.

The Danish report lists the following chemicals and classes of
chemicals as known to have estrogenic activity:

Organochlorine pesticides: DDT, DDD, DDE, dicofol, perthane,
methoxychlor, chlordane, oxychlordane, trans-nonachlor,
heptachlor, heptachlorepoxide, aldrin, dieldrin,
hexachlorobenzene, hexachlorocyclohexanes, lindane (gamma HCH),
mirex, and toxaphene. Although these chemicals have been banned
in several industrial countries, including the U.S., some of them
are still manufactured [in the U.S. or overseas, by U.S.
corporations--PM] and sold in developing countries where they are
"widely used" today, the Danish report says.

Other known estrogenic chemicals include:

** Many of the 109 types of PCBs (polychlorinated biphenyls);

** Dioxins and furans (unwanted by-products of all incinerators;
paper-making mills; metal smelters; and the manufacture of some
chemicals and pesticides);

** Alkylphenols, the breakdown products of alkylphenol
polyethoxylates (APEs) which are widely used in detergents,
paints, herbicides and cosmetics. Some 300 million kilograms
(660 million pounds) of APEs are produced each year and
ultimately released into the environment.

** Phytoestrogens, or plant-produced estrogens, including
isoflavones and coumestans found in rye, wheat, cabbage, sprouts,
spinach and soybeans. "Soybean is far and away the richest
source of plant estrogens and is used ubiquitously [everywhere]
in the food industry as a protein source including the production
of infant milk formula substitutes," the Danish report says.
Depending upon the dose, phytoestrogens have an estrogenic, or an
anti-estrogenic, effect, the Danish report says. Unlike many of
the other estrogenic chemicals identified in the Danish report,
phytoestrogens do not bioaccumulate or biomagnify, but are
readily metabolized and excreted.

** Many common chemicals found in plastics, in-cluding
bisphenol-A, phthalate esters (butylbenzyl phthalate and
di-n-butylphthalate): "Phthalates are the most abundant man-made
environmental pollutants, and human intake per day via various
routes, especially via the diet, is measured in tens of
milligrams," says the Danish report. Some plastics contain up to
40% phthalate esters (by weight). These esters leach out of, or
volatilize out of, the plastics as time passes. Many foods in
the U.S. and elsewhere are packaged in phthalate-containing
plastics. Even blood for transfusions is sometimes packaged in
phthalate-containing plastics.

** Herbicides, such as the popular crab-grass and dandelion
killer, 2,4-D, and the now-banned 2,4,5-T, both of which were
widely used by U.S. forces in Vietnam. (See REHW #436.) Other
herbicides with estrogenic effects include: alachlor; amitrole;
atrazine; metribuzin; and trifluralin.

** Fungicides: benomyl and its principal breakdown product,
carbendazim, used on apples and bananas, among other food crops;
and ethylene bis dithiocarbamates (EBDCs, including mancozeb,
maneb, metiram, and zineb).

** Hexachlorobenzene. Although this pesticide was banned in many
countries in the 1970s, it "continues to be released to the
environment as a byproduct and contaminant in many other
chlorinated chemicals including chlorinated solvents," the Danish
report says.

** Tributyltin compounds. Tributyltin compounds, until very
recently, were used in large quantities as antifouling paints on
ships, boats, and mariculture pen nets. Now banned in many
countries.

** Malathion, heavily sprayed around residential areas of the
U.S. to kill nuisance mosquitoes.

And finally the Danish report warns that exposure to low levels
of many chemicals may be harming the reproductive health of
humans and wildlife by mechanisms that have nothing to do with
estrogen: "Although not the subject of this report, in
considering and evaluating the possible role of estrogenic
chemicals in male reproductive disorders, it should not be
forgotten that many chemicals may have a detrimental effect on
male reproductive health through other mechanisms than an
estrogenic effect," the Danish report says.
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--Peter Montague
===============[1] Our thanks to Lisa Finaldi of Greenpeace International for
helping us obtain a copy of the Danish EPA report.